Fires can break out, in many different situation, due to smoker's carelessness. Examples of such careless are when a smoker, during smoking, throws away his lit cigarette while walking, or throwing a lit cigarette out of a moving vehicle. Additionally if a smoker falls asleep with his lighted cigarette, a fire could start. When a smoker is walking, not only the smoker's carelessness but also the absence of a suitable and convenient extinguishing article, such as an ashtray, can result in a fire.
To prevent such accidents, Japanese Utility Model Kokai Hei 6-46497 proposed a convenient automatic extinguishing wrapper adapted to be used by being wrapped around a cigarette.
This known device comprises two layers: an extinguishing band 11, such as an aluminum foil or ceramic paper, having a fixed length L which is sufficient to be wrapped substantially one turn around the circumferential surface of a cigarette C, and a heat shrinkable band 12, such as a plastic film or a shape memory alloy, bonded to the said extinguishing band 11. This article is adapted to be wrapped around the circumferential surface of the cigarette C with the extinguishing band 11 placed inside.
According to the arrangement of this known configuration, when it is being used wrapped around the cigarette C, as soon as the fire ball or burning head moving from the tip of the lighted cigarette C toward its root reaches the wrapped position, the extinguishing band 11 creates a lack of oxygen in which contact with the open air is broken off. Furthermore, the heat shrinkable band 12 receiving heat from the extinguishing band 11 diametrically shrinks of itself to wrap around and hold down the extinguishing band 11; thus, the article may be said to be advantageous in that it can reliably and naturally extinguish the cigarette C.
However, as a result of continuing research since the development of the known device employing a readily available aluminum foil as said extinguishing band 11 and a heat shrinkable polyethylene film as said heat shrinkable band 12, I have found that the following problems remain to be solved.
The results of the tests on the known device reveal that the assembly of the aluminum foil 11 and the heat shrinkable film 12 bonded thereto forms nothing but a simple cylindrical body having a ore diameter corresponding to the circumferential surface of the cigarette C. The surface of the aluminum foil 11 in contact with the cigarette C is smooth; thus, when a smoker is smoking the cigarette by holding the latter between his or her fingertips, the assembly accidentally slips lengthwise along the cigarette C to change the wrapping position (desired position for extinguishment), so that the cigarette may erroneously be extinguished.
Particularly, the smoker's sweaty fingertips can stick to the heat shrinkable film 12 on the outside, making the above problem more significant. Though not erroneously extinguishing the cigarette, this article held between fingertips for smoking dives a feeling of discomfort.
Further, since the surface of the aluminum foil 11 in contact with the cigarette C is smooth and since the whole including the heat shrinkable film 12 is only of simple cylindrical form, the heat shrink force of the heat shrinkable film 12 cannot act quickly and efficiently as a wrapping and holding-down force for the cigarette C through the aluminum foil 11, so that it takes a long time for the cigarette C to extinguish completely.
On the other hand, since the heat of the cigarette C is propagated to the heat shrinkable film 12 on the outside through the aluminum foil 11, it is heated to a substantial high temperature. As a result, it is difficult, for example, for a smoker to manually forcibly distinguish his cigarette as by instantaneously crushing it with fingertips, and such operation entails a danger of skin burn.
With regard to this point, Japanese Utility Model Publication Sho 55-21600 discloses an automatic extinguishing article for cigarettes comprising three layers: a metal foil 1, paper 2 and a heat shrinkable film 3. In this case, the surface of the metal foil 1 in contact with a cigarette 4 is smooth, and said total of three layers only constitute a simple cylindrical form. Furthermore, since the heat shrinkable film 3 is exposed to the outside, the article slips along the cigarette 4 and likewise tends to catch the smoker's sweaty fingertips, causing a feeling of discomfort.
Particularly, in the arrangement of this known utility model, since the paper 3 is interposed between the metal foil 1 and the heat shrinkable film 3, the paper 3 reduces the heat shrink performance of the heat shrinkable film 3, degrading the extinguishing swiftness with which the cigarette 4 goes out completely.